It enables communication and data transfer between these networks. 

• Protocol Conversion: One of the primary functions of a gateway is to convert data formats or protocols from one network to another. This is essential when networks use different communication protocols or data formats.

• Connecting Different Networks: Gateways are used to connect networks that may be based on different technologies. For example, a gateway can connect a local area network (LAN) to the Internet or an office network to a mainframe computer.

• Data Routing: Gateways often include the functionality of routers, forwarding data packets between networks based on their destination addresses.

• Security and Filtering: In many cases, gateways also provide security functions, such as firewalls, to control the traffic between the networks and protect them from unauthorized access or cyber threats.

Gateways play a crucial role in ensuring that different networks, often with their own unique configurations and protocols, can communicate and exchange data effectively. They are essential components in complex network architectures, supporting the integration and interoperability of diverse systems.